This invention relates to a portable fireplace heating unit. More particularly this invention discloses an enclosed wood-burning fire-box which is easily installed in an existing fireplace opening. Further, the heating unit which greatly increases the heating efficiency of a standard fireplace, has a damper system which cooperates with the existing fireplace damper and flue system.
The recent shortages of fuel for heating homes have created the need not only to conserve resources but also to make better use of existing fuel resources in addition to finding and exploiting new sources of energy.
One of the oldest forms of heat energy, firewood, has in recent times been put aside for more convenient fuels such as gas and oil. However, with the ever increasing shortages of the more traditional fossil fuels, and with the knowledge that wood suitable for burning to provide heat is in plentiful supply in many areas, it is very advantageous to provide systems that would fit into existing fireplace constructions that would increase the heating efficiency of burning wood, coal or similar fuel.
Conventional fireplaces create strong drafts which draw heat from the room right up the chimney. This condition actually lowers the temperature in the other areas of the house away from the vicinity of the fire, and sometimes causes automatic thermostats to activate conventional heating systems to counteract this cooling effect.
The prior art has provided for supplemental heating units to be installed in existing fireplace systems. For example see Goulding U.S. Pat. No. 2,791,213; Craig U.S. Pat. No. 2,258,882; Barber U.S. Pat. No. 2,497,486; Morgan U.S. Pat. No. 2,196,934; Baruck et al U.S. Pat. No. 2,046,051 and Forbes U.S. Pat. No. 1,309,024; Meier U.S. Pat. No. 1,546,503; Newton U.S. Pat. No. 2,172,711; Holz U.S. Pat. No. 2,120,977; Baruch et al U.S. Pat. No. 2,048,675; Johnston U.S. Pat. No. 1,336,700; Robinson U.S. Pat. No. 551,651; Lewis U.S. Pat. No. 463,061; and Jackson U.S. Pat. No. 394,653; but none offers the combination of conveniences that I have provided in my fireplace heating unit.
It is thus the main object of this invention to provide a portable fireplace heating unit wherein an adaptable damper system allows the unit to be quickly and easily installed in an existing fireplace, and when not needed the unit may be easily removed and rolled to a storage area. This heating unit further causes air from the room to circulate around the firebox but not up the chimney. This heated air is then re-directed into the room area, providing a source of heat. Due to the geometry of the heating unit, this circulation of air under and around the firebox is greatly enhanced so that free convection of air is maximized. Thus, although Johnson and Meier teach fireplace enclosures incorporating air vent holes around the side and top of their stoves, none of these patents teach the very important aspect of having vent holes beneath a firebox in order to allow the cold air normally found at or near the floor of a room to enter along the bottom of the fireplace enclosure and thereby promote free air convection. This free air convection is also dependent on the spacing and geometry of the heating unit firebox with respect to the walls of the fireplace. Neither Johnston nor Meier disclose an apparatus for insertion into a fireplace enclosure that has the proper shape and spacing from the enclosure to efficiently promote free air convection.
Furthermore, a self-contained enclosure version of the present invention allows the portable heating unit to be used in a home that has no fireplace. In this version of the invention, the portable heating unit mates with a self-contained enclosure that may be placed anywhere within a home that is near a chimney. A triangular-shaped flue of the self-contained enclosure interconnects with an adjoining chimney to allow the escape of combustion exhaust gases. Due to the thermal insulation of the enclosure, as well as the manner in which the heating unit mates with the enclosure, the outside wall temperature of the self-contained enclosure is low enough to allow placing it in a home without need for special heat resistant masonry. If the flue is placed within a decorative enclosure, air vent holes or a double-walled chimney may be used to exhaust heated air from within the enclosure.
In addition, the heating unit may include a heat radiator that interconnects with the hot water heating system of a home and is able to provide auxiliary heating of this hot water when the home furnace is inoperable.
Further features and other objects and advantages of this invention will become more apparent from the study of the following detailed description with reference to the drawings.